Abstract

Proton Transfer Reaction Mass Spectrometry (PTR-MS) is a well-established technique for real-time VOCs (Volatile Organic Compounds) analysis. Although, it is extremely sensitive (with sensitivities of up to 4500 cps/ppbv, limits of the detection < 1 pptv and the response times of approximately 100 ms) the selectivity of PTR-MS is still somewhat limited, as isomers cannot be separated. Recently, selectivity-enhancing measures, such as manipulation of drift tube parameters (reduced electric field strength) and using primary ions other than H3O+, such as NO+ and O2+ have been introduced. However, monoterpenes, which belong to the most important plant VOCs, still cannot be distinguished so that more traditional technologies, such as gas chromatography mass spectrometry (GC-MS), have to be utilized. GC-MS is very time consuming (up to 1 h) and cannot be used for real-time analysis.
Here we introduce a sensitive, near real-time method for plant monoterpene research: PTR-MS coupled with fastGC. We successfully separated and identified six of the most abundant monoterpenes in plant studies (α- and β-pinenes, limonene, 3-carene, camphene, and myrcene) in less than 80 s, using both standards and conifer branch enclosures (Norway spruce, Scots pine and Black pine). Five monoterpenes usually present in Norway spruce samples with a high abundance were separated even when the compound concentrations were diluted to 20 ppbv. Thus, fastGC-PTR-ToF-MS was shown to be an adequate one-instrument solution for plant monoterpene research.

Metrics

Altmetrics from Altmetric

Citations from Dimensions

Download history for this item

These details should be considered as only a guide to the number of downloads performed manually. Algorithmic methods have been applied in an attempt to remove automated downloads from the displayed statistics but no guarantee can be made as to the accuracy of the figures.